The present invention relates generally to fasteners and more particularly to a nut that is captive to a bolt after assembly therewith.
Notwithstanding the fact that most nuts used in the aircraft industry are provided with a prevailing torque or other locking means, certain applications on an aircraft require that the nut be incapable of separation from a mating bolt. In addition, where discrete locking elements or washers are used, such auxiliary elements are preferably permanently captured both prior to and after installation of the nut on a bolt, to maximize assembly efficiency and preclude inadvertent disassociation.
Captive nuts heretofore known and used generally comprise an annular internally threaded nut body having a deformable portion that engages an annular recess in the shank or threads of a bolt to preclude disassociation after assembly with the bolt. When the nut is torqued down against a workpiece, the deformable portion thereof moves radially inwardly into the recess in the bolt. While such nuts exhibit satisfactory structural integrity the cost thereof is prohibitive and no provision is made for the capture of auxiliary elements prior to assembly with a bolt.